Skip to content
Fairfield Circuitry 20% More Slew Limiting Distortion

Fairfield Circuitry 20% More Slew Limiting Distortion

by Fairfield Circuitry
$539.00
IN STOCK
Love it, or swap within 14 days | Free Gravity Pick!
Afterpay
4 interest-free payments of $134.75 More info

Free Shipping for orders over $199

Orders usually arrive in 2 - 3 days

Free if spend over $199. Large Packages excluded

Love it, or swap within 14 days

Don't like what you hear? No worries - swap within 14 days.

Best service in town

4.8 / 5 from over 500+ Google Reviews Buy from the best in AUS.

Explorations around a schematic found among old papers of mysterious origin, suspiciously similar to a datasheet sq/tri oscillator.
All that was needed was to connect the dots.

A slew limiter smoothes out how quickly incoming voltage can change, limiting it to a fixed v/sec. slope. Since time and frequency are intrinsically linked, this acts as a steep, somewhat distorted low pass filter.

When it resonates, these fixed slopes become triangle wave oscillations, giving 20% more its unique sound. Input signals can overwhelm this oscillation, making for pseudo-wavefolding and synthetic distortion artifacts. 

jfet clipping, sub and upper octaves, envelope follower, low pass gate; impressions, ideas, pleasures and pains
This topology can result in quite a dark sound when SLEW is low, as there will not be much harmonic content present beyond the cutoff frequency. You can use BLEND to mix in a square wave signal that can help bring back some higher harmonics.

LOW PASS GATE

20% More has a slightly resonant, 2 pole, 12dB/oct low pass filter at it's output. It offers a nice counterbalance to the grit of the slew limiter, and allows tasteful reigning in of the crackling potential present in the circuit.

ENVELOPE FOLLOWER

There is a simple internal envelope, its main purpose is to allow high feedback settings while avoiding (possibly unwanted) oscillations when no input is present. Both envelope destinations achieve this through different means.

When the envelope goes to the LPG, it is a bit like a sidechain input, where your playing dynamics open up the filter and let highs pass through, giving some nice springy west coast bongos; the LPG knob needs to be set low for the gating to be effective.

When the envelope goes to FEED, the average feedback is lowered slightly, loud playing will bring it back up. As loud inputs also fight the oscillations, interesting swashes of noise arise as your notes decay.

Two flip-flop based clock dividers, giving sub-octave and sub≠ sub-octave effects. It is only heard when BLEND is up somewhat. The sub octave is summed through diodes, giving it a characteristic 75% pulse.



Play with INPUT. Interactions become intuitive.

FULL WAVE RECTIFIER

Envelope following requires a strictly positive input voltage. To achieve this, a full wave rectifier circuit is used. It is repurposed in the audio path as a switchable octave up. This particular implementation squishes very hard when INPUT is beyond noon. Enjoy.

CONTROLS
:::

INPUT 'mu amp' jfet preamp, lots of gain

BLEND  mixes in a square wave/ sub-octave copy of the signal

VOLUME  output volume, gets very loud

SLEW  slew limiter frequency

FEED  slew limiter feedback

LPG  low pass filter

D - OCTAVE DOWN clock division of the blended square wave, -1 or -2 oct

U - OCTAVE UP analog octave up, full wave rectifier

E - ENVELOPE DESTINATION routing of the internal envelope, either added to the (L)PG or (F)EED controls


INTERNAL CONTROLS
There are two user adjustable trimpots inside the pedal; they are labeled TR3 (drive) and TR2 (sens). The two other trimmers set the jfet bias and v/oct calibration, they should not be adjusted by the user.

DRIVE
sets the amount of signal going into the JFET clipping stage, another 20% more?

SENS(ITIVITY)
Sets the gain of the internal envelope, allowing you to attenuate or exaggerate the response to your playing dynamics.

TECHNICALS

dimensions: 4. 7" X 3.8" X 1.9"

cv input range: 0 - 5v normal ; 0 - 8v max 9VDC
power supply: 20 mA@ 9.6 VD

Warranty & Returns

All New products are covered by the manufacturers new warranty. Please check their website for the length of warranty and warranty conditions. If an item you receive is faulty get in touch with us ASAP. Second Hand products come with a 4 week warranty from us. If there is an issue let us know ASAP! This covers normal use and does not cover accidental damage, misuse, wrong power plugged into it, modding, water damage or any other damage caused by mistreatment. Just treat it nice and all will be good!

Shipping

We send A LOT of packages every week so don't worry about the shipping side of things!

We've never lost a thing and your awesome new gear will be packed up really well to avoid any damage in transit.

If your order comes in before 2pm we will ship it same day. Most of the time we pack things up all the way to 4pm so just call if you need it to leave same day after 2pm.

We ship mainly with Australia Post but may use a courier depending on location and size of the package.

Free Post ships with Australia Post standard and expected shipping times are between 4-6 business days depending on location. It will be longer to outside of metro and rural areas.

Express Post will usually be with you next business day in metro areas of QLD, NSW, SA, VIC and TAS. WA will take 2 days to metro and extra days after that to out side metro and rural areas.

Everything we ship has a tracking number with the exception of some power cables and smaller envelope packages. You will be emailed tracking once your order has been shipped!

Videos

Explorations around a schematic found among old papers of mysterious origin, suspiciously similar to a datasheet sq/tri oscillator.
All that was needed was to connect the dots.

A slew limiter smoothes out how quickly incoming voltage can change, limiting it to a fixed v/sec. slope. Since time and frequency are intrinsically linked, this acts as a steep, somewhat distorted low pass filter.

When it resonates, these fixed slopes become triangle wave oscillations, giving 20% more its unique sound. Input signals can overwhelm this oscillation, making for pseudo-wavefolding and synthetic distortion artifacts. 

jfet clipping, sub and upper octaves, envelope follower, low pass gate; impressions, ideas, pleasures and pains
This topology can result in quite a dark sound when SLEW is low, as there will not be much harmonic content present beyond the cutoff frequency. You can use BLEND to mix in a square wave signal that can help bring back some higher harmonics.

LOW PASS GATE

20% More has a slightly resonant, 2 pole, 12dB/oct low pass filter at it's output. It offers a nice counterbalance to the grit of the slew limiter, and allows tasteful reigning in of the crackling potential present in the circuit.

ENVELOPE FOLLOWER

There is a simple internal envelope, its main purpose is to allow high feedback settings while avoiding (possibly unwanted) oscillations when no input is present. Both envelope destinations achieve this through different means.

When the envelope goes to the LPG, it is a bit like a sidechain input, where your playing dynamics open up the filter and let highs pass through, giving some nice springy west coast bongos; the LPG knob needs to be set low for the gating to be effective.

When the envelope goes to FEED, the average feedback is lowered slightly, loud playing will bring it back up. As loud inputs also fight the oscillations, interesting swashes of noise arise as your notes decay.

Two flip-flop based clock dividers, giving sub-octave and sub≠ sub-octave effects. It is only heard when BLEND is up somewhat. The sub octave is summed through diodes, giving it a characteristic 75% pulse.



Play with INPUT. Interactions become intuitive.

FULL WAVE RECTIFIER

Envelope following requires a strictly positive input voltage. To achieve this, a full wave rectifier circuit is used. It is repurposed in the audio path as a switchable octave up. This particular implementation squishes very hard when INPUT is beyond noon. Enjoy.

CONTROLS
:::

INPUT 'mu amp' jfet preamp, lots of gain

BLEND  mixes in a square wave/ sub-octave copy of the signal

VOLUME  output volume, gets very loud

SLEW  slew limiter frequency

FEED  slew limiter feedback

LPG  low pass filter

D - OCTAVE DOWN clock division of the blended square wave, -1 or -2 oct

U - OCTAVE UP analog octave up, full wave rectifier

E - ENVELOPE DESTINATION routing of the internal envelope, either added to the (L)PG or (F)EED controls


INTERNAL CONTROLS
There are two user adjustable trimpots inside the pedal; they are labeled TR3 (drive) and TR2 (sens). The two other trimmers set the jfet bias and v/oct calibration, they should not be adjusted by the user.

DRIVE
sets the amount of signal going into the JFET clipping stage, another 20% more?

SENS(ITIVITY)
Sets the gain of the internal envelope, allowing you to attenuate or exaggerate the response to your playing dynamics.

TECHNICALS

dimensions: 4. 7" X 3.8" X 1.9"

cv input range: 0 - 5v normal ; 0 - 8v max 9VDC
power supply: 20 mA@ 9.6 VD

Warranty & Returns

All New products are covered by the manufacturers new warranty. Please check their website for the length of warranty and warranty conditions. If an item you receive is faulty get in touch with us ASAP. Second Hand products come with a 4 week warranty from us. If there is an issue let us know ASAP! This covers normal use and does not cover accidental damage, misuse, wrong power plugged into it, modding, water damage or any other damage caused by mistreatment. Just treat it nice and all will be good!

Shipping

We send A LOT of packages every week so don't worry about the shipping side of things!

We've never lost a thing and your awesome new gear will be packed up really well to avoid any damage in transit.

If your order comes in before 2pm we will ship it same day. Most of the time we pack things up all the way to 4pm so just call if you need it to leave same day after 2pm.

We ship mainly with Australia Post but may use a courier depending on location and size of the package.

Free Post ships with Australia Post standard and expected shipping times are between 4-6 business days depending on location. It will be longer to outside of metro and rural areas.

Express Post will usually be with you next business day in metro areas of QLD, NSW, SA, VIC and TAS. WA will take 2 days to metro and extra days after that to out side metro and rural areas.

Everything we ship has a tracking number with the exception of some power cables and smaller envelope packages. You will be emailed tracking once your order has been shipped!

Related Products